1. Field of Invention
The present invention relates generally to the field of woodworking, more specifically to cabinet and furniture making, and relates to a system for holding a workpiece in place with sliding guide rails that are tightened down in strategic places so that a hand held power tool can perform the needed task.
2. Prior Art
Prior art teaches that the router is the best solution for cutting clean dados and grooves. The reason for using a router over other tools such as a table saw would be that a router bit is cutting across the grain while the table saw blade is rotating downward. This downward rotation will pull the veneer down and away from the substrate that the veneer is glued to. This pulling down and away from the substrate causes the veneer to break off and leave the substrate underneath the veneer exposed, thus leaving an undesirable result on the workpiece.
(A) Other prior arts have attempted to make dadoing easier and a more efficient operation. One such prior art would be U.S. Pat. No. 5,682,934 patented on Nov. 4, 1997—Class 144/Sub-Class 144.51 to Richard C. Rybski, which teaches a system that has a base, which a router or other power tools can ride between two angle irons. While this will give a clean dado and a straight cut, the operator will have to stop and reset the system for each dado or cut made. Also the cutouts for the hold-downs are placed so that the operator must position the workpiece in a fashion where the workpiece can be held down without the hold-downs being in the way of the router or tool being used. Another problem with this system is there is no place for calibrated measurement means to help in the setup of the workpiece in relation to the tool guide. This will make it very hard and time consuming to make accurate repetitive cuts or dados.
(B) Another prior art would be patent No. 4,966,507 patented on Oct. 30, 1990—Class 409/Sub-Class 175 to Robert Hanks. One problem with this router jig is that the clamping mechanism comprising of two boards that hold the workpiece in place are adjustable and therefore will need careful attention during the setup process to make sure that the workpiece is square to the base plate portion of the jig. Another problem with the jig is the horizontal and vertical guides. Even though the guides are adjustable with a suitable calibrated measurement means on them, it will still be difficult to insure that the guides are square to the workpiece. The reason for this is that both the vertical and horizontal guides will have some play in them since they are adjustable. This play on the guides can cause the calibrated measurement means to be off, making it possible for the dados to be out of square on the workpiece.
(C) U.S. Pat. No. 3,770,031 patented on Nov. 6, 1973—Class 144/Sub-Class 136 R to Eugene T. Olson for a routing fixture. This fixture will have to have repeated setups for each dado that is cut into the workpiece. This is time consuming and it will be very difficult to align the workpiece and the bit that is in the router to the precise area that is marked for the dado on the workpiece. It also would be very hard to cut perfectly matching dados in a workpiece.
(D) U.S. Pat. No. 4,215,731 patented on Aug. 5, 1978—Class 144/Sub-Class 136 C to Douglas E. Maynard for a router guide assembly. One problem with this router guide is that the workpiece must be moved after each dado is made. Then the workpiece must be moved to line up with the notch in the fence so that the bit is not damaged as the bit exits the workpiece. Another problem is setting up the depth of the router bit. The operator of the router must allow for the extra distance between the router carriage and the workpiece. There also is a problem as far as lining the workpiece up with the with the router bit because there are no calibrated measurement means to help line the workpiece up with the router bit.
(E) U.S. Pat. No. 5,533,556 patented Jul. 9, 1996—Class 144/Sub-Class 144.52 to David Whitney for a router guide apparatus. While this apparatus is portable, you must clamp the guide on each workpiece that needs a dado cut into it. This means that the apparatus must be clamped on each workpiece multiple times and great care must be given to the placement of the guide on each workpiece so that the matching dados will line up properly. This is quite time consuming and would be very hard to use in a production type setting.
While all of these dadoing jigs do have a limited ability for making straight dados or grooves, these jigs require a new setup for each dado that is required on a workpiece. Also with these jigs, it is quite difficult to be sure that the workpiece is positioned in the exact same place as the previous workpiece. If the workpiece is not set up the same as the previous workpiece this could result in the dados not lining up properly when the workpieces are assembled. This shows that there is a need for a system that can make one or more repeatable dados on a workpiece and that does not take much time or effort to set up.